1. Field of the Invention
This invention relates, generally, to the medical field. More particularly, it relates to the field of brachytherapy.
2. Description of the Prior Art
In the field of brachytherapy, which relates to the placing of radioactive seeds and non-radioactive spacers in the prostate and other internal organs, it is advantageous to maintain the seeds and spacers of a seed train in alignment with one another after implantation. Loose seeds have a tendency to migrate a few millimeters after placement. If the seeds and spacers in the train are not coupled to one another, the seeds may move and turn within the prostate after implantation. If that happens, the seeds will be misaligned with one another when a radiograph is taken. The radiograph is important because every seed needs to be accounted for. If the seeds are in a straight line, they are easy to count. If they are jumbled, counting becomes more difficult.
A commercially available device, sold under the trademark Rapid Strands by Nycomed Amersham, uses suture material to encapsulate the members of the seed train. Moreover, there are various implantable tubes, strands, or other methods in the marketplace that encapsulate the seed/spacer train and that limit the movement of the seeds relative to one another.
However, the known techniques are somewhat expensive and some of the known techniques do not reliably couple the members of a seed train to one another.
What is needed, then, is a low cost and highly effective way of coupling together the members of a seed train.
However, in view of the prior art considered as a whole at the time the present invention was made, it was not obvious to those of ordinary skill in the pertinent art how these needs could be fulfilled.